This invention relates to a self propelled irrigation sprinkler. More specifically, this invention relates to an impeller driven sprinkler which traverses an area to be watered.
It is often desirable to water large areas of a lawn. One common method to accomplish this aim is installation of underground pipes with sprinklers which are placed to insure that all areas of the lawn have coverage. This method is effective, however it is expensive and time consuming to install the pipes and sprinklers in the ground. Furthermore, it is difficult to change the location of sprinklers should various features of the area change.
Another inexpensive method for watering a lawn area involves using a garden hose with a sprinkler. The sprinkler is fluidly driven and distributes water in a designed geometric pattern. Examples of sprinklers include an oscillator arm sprinkler type or a spray pattern irrigation device. The garden hose is connected to a spigot which supplies water to the sprinkler under pressure. The proportion of the water flow from the spigot may be regulated by turning a knob.
A user typically connects one end of the hose to the spigot, attaches the sprinkler to the other end of the hose and places the sprinkler in the area desired to be watered. The user then turns on the water flow from the spigot by turning the knob. The water flow is forced through the hose and distributed by the sprinkler to the desired area. In this manner, areas which are distant from the spigot may be watered. By regulating the flow rate from the spigot, the user may also alter the speed of the sprinkler and the distance it throws water in the area. After the sprinkler is set up in the desired location, the user is free to attend to other tasks while the area is watered.
This method provides an inexpensive alternative to a permanent irrigation system as a user may move the sprinkler to the areas where watering is needed. However, compared to permanent irrigation systems, this method is much more labor intensive, especially for large areas. One solution which has been proposed for areas which are too large to be irrigated with one fixed sprinkler is a wheeled sprinkler which is self propelled and reels in hose as it travels across an area toward the spigot. Such a sprinkler uses the water pressure to turn a rotating sprinkler head and uses this rotational force to propel the wheels of the sprinkler. Reduction gearing connected to the sprinkler head is attached to the wheels to achieve a relatively slow speed to insure proper watering of the area. This sprinkler head has a pair of arms which rotate and discharge water at their ends thus creating coverage over a certain defined width along the path of the sprinkler. Unfortunately, such sprinklers suffer from the inability to water irregularly shaped areas since the rotating sprinkler head can only water in one circular pattern.
Thus, there exists a need for a self propelled sprinkler which allows watering of large areas using an efficient propulsion means. There also exists a need for a self propelled sprinkler which provides the use of different spray heads independent of the propulsion of the sprinkler. There is also a need for a self propelled sprinkler which follows a hose for its path.
These needs and others may be met by the present invention which is embodied in a self propelled sprinkler unit for irrigation of a ground area and connection with a hose connected to a pressurized water source. The sprinkler unit has a drive unit having a hose inlet with a hose coupler. The drive unit having a drive chamber with a rotatable impeller in fluid contact with the water flow from the hose inlet. A shaft is mechanically coupled to the impeller. The sprinkler unit has a pair of rear wheels with at least one rear wheel coupled to the shaft. An outlet coupler is in fluid communication with the drive unit. A sprinkler head is coupled to the outlet coupler.
The invention may also be embodied in a water propelled drive unit for a self propelled sprinkler with a hose coupled to a water source. The drive unit has an enclosed drive chamber with a cylindrical shape having two relatively flat ends, an outer surface, and an inner surface. An inlet coupler is located on the exterior surface of the drive chamber allowing fluid communication to the drive chamber. A shaft is mounted between the two flat ends. A rotatable impeller is mounted axially on the shaft in the drive chamber. The impeller is in fluid contact with the inlet coupler and is rotatably coupled to the shaft. An outlet coupler is mounted on the exterior surface of the drive chamber.